A patient presenting with cervical lymphadenopathy and night sweats warrants which diagnostic next step?

In a patient with cervical lymphadenopathy and night sweats, the clinical presentation raises concern for a possible malignancy or infectious process, particularly lymphoma or metastatic disease. The gold standard for diagnosing lymphadenopathy when there is a suspicion of cancer is obtaining a tissue sample for histological evaluation, which can be accomplished through an excisional biopsy of the lymph node.

An excisional biopsy allows for the complete removal of the lymph node, providing a larger sample of tissue that can be examined thoroughly for malignancy or specific infectious agents. This method is superior to other forms of biopsies, such as fine needle aspiration, because it offers more tissue for evaluation, including architecture and cell types, which are critical for an accurate diagnosis.

While imaging studies such as a CT scan can provide valuable information about the extent of disease and identify additional lymphadenopathy, they do not provide definitive diagnostic information. Fluorescence immunophenotyping is a specialized test that may be performed later to further characterize any identified lymphoproliferative disorder but is not a primary diagnostic tool.

Therefore, the most appropriate next step in managing a patient with cervical lymphadenopathy and night sweats is to perform a lymph node excisional biopsy to establish a definitive diagnosis.